Dounia Bouzar, shown here in 2015, helps parents in France who want to prevent their kids from joining militant groups like ISIS — whose recruiters, she says, "set out to break every emotional, social and historical tie in the kids' lives." Charles Platiau/Reuters hide caption
Mourad Benchellali speaks to a group of students and parents in Strasbourg, France. In 2001 Benchellali traveled to Afghanistan to visit his brother, and was forced into an al-Qaida training camp. He now speaks out against radical Islam. Courtesy of Mourad Benchellali hide caption
A video produced by Exit-Deutschland describes the work it does to de-radicalize neo-Nazis. Hayat Germany is trying to use similar techniques to help Germans who may be radicalized by groups like the Islamic State. ExitDeutschlandVideo via YouTube/Screenshot by NPR hide caption
The picturesque town of Odense — the birthplace of Hans Christian Andersen — is one of the Danish cities battling ISIS and its recruitment efforts. Denmark has one of the worst radicalization problems in Europe. Joao Alves/Flickr hide caption
Latifa Ibn Ziaten, shown here speaking to French elementary schoolchildren in March, started an organization to prevent radicalization after her son, a French soldier, was killed by an Islamist gunman in March 2012. Pascal Pavani/AFP/Getty Images hide caption
British police dog handlers patrol a train station in London in January. Matt Dunham/AP hide caption